Laminating method for honeycomb

ABSTRACT

There is described a novel method and a laminating machine useful to perform said method, all for the production of unexpanded honeycomb laminate, which machine includes a printing stage for application of adhesive upon the upper and lower faces of the upper one of a pair of webs transverse to the direction of travel of said webs and in the form of spaced parallel lines; said printing stage including means for laminating the printed one of said pair of webs to the clean web during the application of the adhesive; a tractive or draw stage which receives the printed, laminated pair of webs from the printing stage and transports same to a severing stage where the webs are cut between the adhesive lines whereat severance of the webs to sheets of predetermined length is accomplished without disturbance of said adhesive lines; the described invention also including a framework for mounting said stages thereon, drive means, including a motor and chain drive, capable of driving the printing and draw stages at a differential rate one relative to the other with the draw stage operated at a slightly greater speed than the printing stage so that the webs are held taut in transport to the severing stage; and, control means for actuating the severing of the webs into said sections of length, said control means being operated as a function of the number of lines of adhesive printed upon one of the upper or lower web faces of said printed web and there being means for compensating for the relative speed of the webs and the inertia of the actual severing means utilized at the severing stage. The severing means at the severing stage is actuated when a predetermined condition being reached, said condition being a function of the number of printed lines and being capable of presetting to any value. A proximity detector is utilized as sensing means in a relay circuit to count the number of lines printed by monitoring the rotation of one of the printing rollers of the printing stage, said count being transmitted to tabulating means which is present to actuate the severing means upon a predetermined count, said circuittabulating means including a DC solenoid valve system for causing movement of the severing means, and also includes means for actuating the severing means while tallying the count to a retallying condition so that counts are not lost during the motion of the severing means. Guide means are described for monitoring and adjusting the alignment of the webs and a pneumatically operated solenoid actuated blade system is provided as the severing means for the severing stage, said system including a fixed blade positioned above the webs and a movable blade position below the webs, a pneumatic cylinder system for actuating the movable blade toward the fixed blade and said solenoid valve system being operable upon said cylinder system to drive the movable blade for severance of the web.

llnite States Patent Jan. 25, 1972 Siegal et a1.

[54] LAMINATING METHOD FOR HONEYCOMB [72] Inventors: Burton L. Siegal, Skokie, 111.; Steve Herndon, deceased, late of Fredericktown, Ohio Nancy Herndon of Frcdericktown, Ohio,

Primary ExaminerSamuel W. Engle ArtorneySilverman & Cass [5 7] ABSTRACT There is described a novel method and a laminating machine useful to perform said method, all for the production of unexpanded honeycomb laminate, which machine includes a printing stage for application of adhesive upon the upper and lower faces of the upper one of a pair of webs transverse to the direction of travel of said webs and in the form of spaced parallel lines; said printing stage including means for laminating the printed one of said pair of webs to the clean web during the application of the adhesive; a tractive or draw stage which receives the printed, laminated pair of webs from the printing stage and transports same to a severing stage where the webs are cut between the adhesive lines whereat severance of the webs to sheets of predetermined length is accomplished without disturbance of said adhesive lines; the described invention also including a framework for mounting said stages thereon, drive means, including a motor and chain drive. capable of driving the printing and draw stages at a difierential rate one relative to the other with the draw stage operated at a slightly greater speed than the printing stage so that the webs are held taut in transport to the severing stage; and, control means for actuating the severing of the webs into said sections of length, said control means being operated as a function of the number of lines of adhesive printed upon one of the upper or lower web faces of said printed web and there being means for compensating for the relative speed of the webs and the inertia of the actual severing means utilized at the severing stage. The severing means at the severing stage is actuated when a predetermined condition being reached, said condition being a function of the number of printed lines and being capable of presetting to any value. A proximity detector is utilized as sensing means in a relay circuit to count the number of lines printed by monitoring the rotation of one of the printing rollers of the printing stage, said count being transmitted to tabulating means which is present to actuate the severing means upon a predetermined count, said circuit-tabulating means including a DC solenoid valve system for causing movement of the severing means, and also includes means for actuating the severing means while tallying the count to a retallying condition so that counts are not lost during the motion of the severing means. Guide means are described for monitoring and adjusting the alignment of the webs and a pneumatically operated solenoid actuated blade system is provided as the severing means for the severing stage, said system including a fixed blade positioned above the webs and a movable blade position below the webs, a pneumatic cylinder system for actuating the movable blade toward the fixed blade and said solenoid valve 7 system being operable upon said cylinder system to drive the movable blade for severance of the web.

5 Claims, 10 Drawing Figures LAMINATING METHOD FOR HONEYCOMB This invention relates generally to apparatus and method for the manufacture of honeycomb and, more particularly, is concerned with the provision of a single machine for printing, laminating, and severing continuous webs of sheet material into lengths of predetermined dimension for the production of unexpanded honeycomb; the machine being characterized by its independence of dimension limitations, its versatility, its increased rate of operation as compared to prior art devices for purposes, and by a decrease of scrap to a degree not heretofore achieved by prior art devices.

Expanded honeycomb is a cellular structural material having advantages of high strength-to-weight ratio useful as a filler and support for structural components in aircraft, missiles, buildings and many other types of structures. The honeycomb material as used consists of sections of opencelled material sandwiched between skins of such sheet materials as aluminum, paper, fiber, and the like. The cells are made by expanding a laminate which may be defined herein as unexpanded honeycomb core. Honeycomb core is marketed to the structural fabricator in the expanded form of predetermined dimensions, weight, cell size and characteristics. The laminate from which the core members are made consists of a multiple number of sheets having spaced parallel lines of adhesive applied thereto, the sheets being arranged in stacks with adjacent sheets having the adhesive lines thereof staggered relative to the lines on the immediate neighboring sheets. With this laminate structure, a hexagonal cell structure results when the unexpanded laminate block is expanded as by pulling upon the top and bottom sheets of the stack subsequent to cure or setting of the adhesive lines. Thereafter other processes will be used to coat, cure, cut, form, etc.

Generally, the sheets utilized to form the unexpanded honeycomb core are produced by applying initially lines of adhesive upon a continuously moving web of sheet material, such as fiber glass cloth, aluminum foil, paper and the like. The cell size desired is maintained by controlling the width of the adhesive lines as well as the spacing therebetween. The length, width and depth dimensions are controlled by selection of web dimensions and precision severing of predetermined lengths of the web subsequent to the printing operation.

In order to provide industry with acceptable honeycomb core structural material the quality control of the process utilized to form the unexpanded honeycomb core is very important. However, also important is the production of the material as an economically competitive product. The latter requirement is characterized by the provision of processes and machinery which meet the criteria involving minimization of waste by proper scrap control, selection of proper dimension web material to take into account tolerances and maximum utilization of the material, precision in cutting so that proper dimensions are held, and others.

Present honeycomb manufacture uses machinery for applying the adhesive lines to continuous webs of sheet material, thereafter severing the webs to predetermined size and manually arranging the thus separated lengths in stacks of a required number. This method is limited by the absence of versatility in the machinery as well as other disadvantages which will be evident during the description hereinafter.

Of the continuous web processes, two general categories were common. The first of these involved the applying of parallel spaced adhesive lines onto the web longitudinally or in other words, parallel to the direction of the travel of the web through the machine. The other category involved the applying of spaced parallel adhesive lines in a direction perpendicular to the direction of the travel of the web.

in the application of adhesive longitudinal of the web direction, ribbon direction L of the finished product was a function of the width of the web, while the T or depth dimension of the finished product was a function of the cutoff length. The W or width dimension, that is, the dimension taken perpendicular to the ribbon direction, was dependent upon the number of sheets utilized to form the stack. Industrial demand became such as to require almost infinite variation in the ribbon dimension, and hence the application of adhesive transverse the web direction became the more generally used method. In transverse application, the (L) or ribbon dimension became a function of the cutoff, while the (T) dimension became a function of the web width and the (W) or width dimension became a function of a number of sheets in a stack.

Accordingly, it is the object of this invention to provide a single machine for the production of unexpanded honeycomb laminate, said machine being more versatile than prior machines for the purpose.

Another object of this invention is to provide a laminating machine. for the production of unexpanded honeycomb laminate which has a printing stage removably mounted to a machine frame, said printing stage characterized by printing rollers having circumferential lands arranged parallel one to the other and to the roller axis for the printing of adhesive lines upon a continuous web transverse the web.

Another object of the invention is to provide a laminating machine for the production of unexpanded honeycomb laminate which includes a printing stage having a pair of printing rollers, each of which is provided with parallel lands spaced circumferentially on the roller and parallel to the axis of the roller, the stage further including pressure rollers, whereby the spaced lines of adhesive are applied to the under surface of one web and subsequently, spaced lines of adhesive are applied to the upper surface of the same web, each between the location of the first lines, and, at the point of application of said second lines, the first web being brought into contact with a second unprinted web to be laminated thereto.

Another object of the invention is to provide in a laminating machine for the production of unexpanded honeycomb laminate, draw means for receiving a printed and laminated continuous pair of webs of sheet material from a printing stage and transporting same to a severing stage, said draw means being driven at a rate slightly greater than rate of drive of the printing stage whereby to cause the delivered web to remain taut during travel to the severing stage.

Another object of the invention is to provide such draw means as above described wherein said draw means is further characterized by means adjustable to accommodate processing of different web widths.

Another object of the invention is to provide a laminating machine for the production of unexpanded honeycomb laminate which is characterized by the inclusion of a printing stage for receiving a continuous pair of webs of sheet materials, imprinting lines of adhesive on upper and under surfaces of one web and laminating said web to the second, unprinted, web; a draw stage for receiving the laminated webs and transporting same to a cutting or severing stage for severing of the webs to lengths of predetermined dimension, drive means, including a singlemotor, operable to drive both printing and drawing stages, and synchronizing means to control the severing of the web as a function of the number of lines of adhesive printed and said synchronizing means, including sensing means operable to determine the number of lines printed.

Other important objects and advantages of the machine and method of the invention are to provide many structural and methodological improvements to the said machine, and include, many novel features of the draw mechanism, namely the pinch-finger assemblies per se and their structure which enable the laminate web positively to be engaged and drawn from the printing and laminating stage of the machine; the relation of severance and timing thereof as a function of the number of lines of adhesive printing upon the web so that the exact length of sheets thus severed may be controlled carefully and precisely, means to prevent tipping of the pinch-finger assemblies as the pinch fingers thereof contact the web, thereby to prevent blousing or gathering of the web; the provision of backup means to supplement the shuttle-bar support for the web as the pinch fingers engage same; the severance of the laminate web by impelling a blade therethrough from the undersurface thereof, again to avoid distortion and prevent severance through areas of the web-carrying adhesive; the use of proximity detector means to monitor the number of lines printed by monitoring the passage therepast of the lands of one or the other of the printing rollers of the printing means; and many other improvements which will become evident as a description thereof ensues in respect of a preferred embodiment of the invention as illustrated in and with reference to the accompanying drawings.

In the drawings:

FIG. 1 is a side elevational view of a laminating machine for use in production of unexpanded honeycomb, said machine being constructed in accordance with the invention and illustrated with portions removed to show interior details.

FIG. 2 is a fragmentary detail of the printing head of the laminating machine of FIG. 1 illustrating the operation thereof.

FIG. 3 is a top plan view of the laminating machine illustrated in FIG. 1 with portions shown in section.

FIG. 4 is a sectional view taken along lines 4-4 of FIG. 3 and in the direction indicated.

FIG. 5 is a fragmentary sectional view taken along lines 5 5 of FIG. 3 and in the direction indicated.

FIG. 6 is a fragmentary detail illustrating the sensing means of synchronizing means provided by the invention to synchronize the severing stage of the laminating machine with a predetermined length of sheet desired.

FIG. 7 is a diagrammatic view of the laminating machine iilustrated in FIG. 1 showing the operation of said machine.

FIG. 8 is a fragmentary detail of the unexpanded honeycomb laminate processed using the sheets produced by the laminating machine illustrated in FIG. 1, portions of said laminate being removed to show internal detail.

FIG. 9 is a fragmentary perspective view of a honeycomb log formed by expanding the unexpanded laminate illustrated in FIG. 8.

FIG. 10 is an electrical schematic for the synchronizing means illustrated in FIG. 6.

Referring now to the drawings, and particularly to FIGS. 1 and 8, the laminating machine constructed in accordance with the invention is generally indicated by reference character 10 and comprises a frame 12, a web guide and feed means 14, a printing and laminating stage 16, a draw stage 18, and a severing stage 20. Synchronizing means 22 (illustrated and described in FIGS. 6, 7 and 10) is provided accurately and precisely to control the severing stage whereby to produce finished laminated sheet lengths of predetermined dimension coordinated with and as a function of the number of imprinted lines of adhesive applied to the web at the printing stage 16. Drive means 24 are provided for operating the stages 16 and 18, including singular motor means 26 and means operable upon said drive means 24 to drive the draw stage 18 at a speed slightly greater than the speed at which the printing and laminating stage 16 is driven thereby to ensure the tautness and proper alignment of the web as it passes through the draw stage 18 in its transport to the severing stage of machine 10.

The frame 12 is of open, rectangular configuration formed of pairs of vertically oriented beam members 30, 32 and 34, bracing members 36 and horizontally oriented beam members 38 and 40. Members 30 are disposed at the entry or source end of the machine 10 and serve to support a portion of the web supply and feed means 14. Members 32 are arranged between the ends of the machine 10 and serve to brace the frame 12 at the location of the printing and laminating stage. Members 34 are arranged at the delivery end of the machine 10 and serve to support the severing stage of said machine. Horizontally oriented members 38 are arranged to form an open bed for the machine 10 while members 40 are arranged to form the base of said machine 10.

The web supply and feed means 14 comprises source rollers 68, 70 and guide rollers 42, 44, 46, 48 and 50, suitably mounted for free rotation in mounting means 52, 54, 58, 60

and 62, suitably secured to the beam pair 30 at the entry end of the laminating machine 10. The uppermost guide roller 42 and its associated mounting means 52 is located, secured to an upwardly, diagonally outwardly extending extension pair 61 of beam pair 30. Rollers 44, 46 and 48 are vertically aligned while roller 50 is offset inwardly from the entry end of the laminating machine 10 spaced at the level of horizontal beam pair 38. The axes of rotation of the rollers 42, 44, 46, 48 and 50 occupy substantially parallel horizontal planes. The rollers 42, 44 and 46 form a guide means for the upper or imprintable web 64 from source 68 while the rollers 48 and 50 serve as guide means for the lower or blank web 66 from source 70, said source rollers 68 and 70 being mounted exterior of the laminating machine 10. The pitch of said rollers 42, 44, 46, 48 and 50 may be adjusted so that the edges of webs 64 and 66 are aligned. Obviously, many known means of assuring web guide and alignment can be utilized to feed web 64 and 66 into rollers 46 and 48, respectively, so that the webs are properly aligned one with the other. The directional flow of the webs into the laminating machine 10 is shown by arrows 72 and 74.

The printing and laminating stage 16 of laminating machine 10 is bodily and removably attached to the horizontal beam pair 38 and extends across the bed of the laminating machine 10. A pair of end plate castings 76 and 78 are provided for supporting suitable mounting means for the respective printing, pressure, doctor and guide rolls comprising the printing and laminating stage 16. A pair of driven printing rolls, namely, upper printing roll 80 and lower printing roll 82 is mounted for rotation between the plates 76 and 78 upon shafts 83 and 84, respectively. A pair of applicator rolls, upper applicator roll 86 and lower applicator roll 88 is mounted between plates 76 and 78 on shafts 90 and 92, respectively, and so that their circumferential surfaces tangentially engage the respective printing rolls along the full length thereof. 4

Doctor rollers 94 and 96 are mounted for rotation on shafts 98 and 100 suitably journaled on plates 76 and 78. The doctor rollers 94 and 96 are arranged so that their circumferential surfaces tangentially are closely adjacent to the circumferential surfaces of the applicator rolls 86 and 88, respectively, and form wells 102 and 104 therebetween for storage of adhesive material intended to be imprinted upon the upper disposed, imprintable web 64. A guide roller 106 is mounted for rotation on shaft 108 rotatably journaled across the bed of the laminating machine 10 on beam 38. The axes of rollers 50 and 106 are substantially in the same plane so that the lower disposed blank web 66 is received from roller 50 for guidance into the printing stage at the desired location.

Pressure roller 110 and 112 are suitably mounted for rotation on shafts 114 and 116 journaled in plates 76 and 78. The circumferential surfaces of pressure rollers 110 and 112 tangentially abut the circumferential surfaces of printing rollers 80 and 82, respectively, said pressure rollers 110 and 112 being formed of a resilient material so that they can exert pressure against webs 64 and 66 as they pass between the respective pressure rollers and printing rollers.

The printing rollers 80 and 82 are characterized by a plurality of raised parallel lands 118 parallel equispaced along the length of the printing rollers. The width of the outer surface 120 of each land is equal to the desired width of the transverse adhesive lines to be printed on the imprintable web 64 normal to the web travel direction. The transverse lines 122 are printed on the undersurface of imprintable web 64 by the lands 118 of roller 82 while the transverse adhesive lines 124 are printed on the upper surface of imprintable web 64 by the lands 118 of printing roller 80. The spacing between lands on each of the rollers 80 and 82 is selected, and, as well, the rollers 80 and 82 are arranged as by the installation of wellknown shaft phase adjuster means (not shown) between the sprocket gear 82 and shaft 84, so that lines 124 are imprinted intermediate the lines 122 so that the unprinted areas aligned on web 64 and 66 are equal in spacing relative to one or the other of the printed lines 122 and 124. The heights of the lands 118 on both printing rollers 80 and 82 are identical.

Only the printing rollers are driven with suitable gearing provided at one end of the respective printing and applicator rollers so that driving of the printing rollers drives in turn the associated applicator rollers. The surfaces of doctor rollers 84 and 96 are closely adjacent at a respective single lateral line with the circumferential surface of the applicator rollers. The spacing determining the thickness of adhesive film applied to said surface and being adjustable. Driving of the roller 82 in a counterclockwise direction will cause roller 88 to rotate in a clockwise direction. As the well 104 defined by the rollers 88 and 96 contains the adhesive, a thin coating of adhesive is imparted to the circumferential surface of roller 88 on rotation thereof. That surface portion of roller 88 will carry the thin film of adhesive to the surface 120 of lands 118 as the said coated circumferential surface of roller 88 comes into contact with the surface 120 of each land 118, the surfaces 120 defining the circumferential surface of both printing rollers.

Likewise, printing roll 80 is driven rotatably by the same drive means that drives roller 82, at the same speed and in a clockwise direction. Accordingly, the applicator roller associated therewith, that is roller 86, rotates in a counterclockwise direction. In the same manner as described relative rollers 88 and 96, adhesive from well 11 2 is applied to the circumferential surface of roller 86 and placed upon the surfaces 120 of lands 118 of roller 80.

Taking the webs 64 and 66 through the web guide and feed means 14 and a printing and laminating stage 16, we note that web 64 is introduced around the underside of roller 46 and travels in a counterclockwise direction over roller 44, then proceeds in a counterclockwise direction over roller 42, entering the printing stage 16 between roller 112 and printing roller 82. The undersurface thereof is provided with the transverse adhesive lines 122 by roller 82 and thereafter the web 64 passes between web 66 and printing roller 88.

Now the blank web 66 is introduced over roller 48, under roller 58, traveling to roller 106 and is fed to be threaded over roller 110 between roller 110 and printing roller 80. The blank web passes between rollers 110 and 80 at the same time that the imprintable web 64 is passing through the same pair of rollers and being imprinted with lines 124 transverse to the web. Accordingly, the blank web 66 is laminated to the undersurface of imprinted imprintable web 64 and thus the laminated web, which will now be referred to as web 65, is illustrated as passing out of the printing stage 16 and has uncovered transverse adhesive lines 124 on the upper surface thereof with no adhesive found on the under surface of the laminate 65.

Obviously, it is highly important that the laminate web 65 be held taut when taken from the printing and laminating stage 16. Said web has to be transported to the severing stage 20 over a considerable distance, and wrinkling should be prevented for obvious reasons.

Accordingly, attention now is directed to the tractive or draw stage 18 of laminating machine which is mounted on the horizontal beam pair 38 bridging the bed of the laminating machine 10. The draw stage 18 comprises a frame formed of vertical support beam pairs 126 and 128 mounted in respective upright parallel relationship on the beam pair 38. Support beam pairs 126 and 128 are provided and may be formed respectively of a pair of blocks vertically stacked; said pairs 126, 128 being spaced one from the other and carry upper shafts 130 and 132 and lower shafts 134 and 136, said shafts being journaled for rotation in suitable means formed on or secured to respective beam pairs 126 and 128. The shafts 132 and 136 carry a set of meshed follower gears 138 and 140, said gears being mounted between the ends of the respective shafts 132 and 136 and the outer surface of one beam of the beam pair 128. Mounted at the end of shaft 132, and either coupled with or integral with gear 138, is a reduction gear 142, the purpose of said gearing arrangement will be evident as a description of the draw mechanism for the laminating machine 10 is explained hereinafter. The frame for the draw stage 18 is completed by two pair of horizontally arranged beam standards secured to respective ones of said beam pairs 126 and 128. These horizontally arranged bracing beam pairs are respectively designated as bracing pairs 144 and 146.

The draw stage 18 includes a draw mechanism generally designated by reference character 148 comprising upper reach, pinch-finger transport system generally designated by reference character 150 and a lower reach shuttle-bar trans port system generally designated by reference character 152.

First, attention is directed to the upper reach pinch-finger transport system 150 which comprises a pair of pinch-finger transport mechanisms, namely, fixed position pinch-finger transport mechanism 154 and a laterally movable pinch-finger transport mechanism 156. Mechanism 154 is arranged so that it is aligned with one border 158 of the laminate web 65 and movable pinch-finger transport mechanism 156 can be positioned on the opposite border 160 of web 65. Both mechanisms 154 and 156 are arranged disposed parallel and coextensive, with the respective individual pinch-fingers thereof likewise arranged so that the pinch-fingers of the fixed mechanism 154 are aligned with the pinch-fingers of the movable mechanism 156. It should be understood that mechanism 154 is adjustable to any reference edge, and thereafter is in a fixed position, that is, a reference position.

Turning to the fixed mechanism 154, a pair of mounting bars 162 and 164 are mounted on shaft 132 by means of bearings 166 and 168 having inner races 170 and 172 through which is journaled shaft 132. Obviously, races 170 and 172 are coaxial and aligned one with the other. A sprocket gear 174 having teeth 176 is mounted between the plates 162 and 164 on shaft 132. Clearly, an identical arrangement is provided for mounting on shaft 130 on the input end of the pinch-finger transport mechanism 154. The plates 162 and 164 are mounted so that they are equally spaced apart and parallel and likewise parallel to the border 158 of web 65, being secured together by fastening means such as bolts 178. A link chain 180 is mounted on sprocket gears 174 extending between shafts 132 and 130 and is engaged on teeth 176. A plurality of pinch-finger assemblies 182 is arranged, mounted fixedly to the links 184 of link chain 180.

Each pinch-finger assembly 182 comprises a pinch-finger housing 186 having a through-axial passage 188, a cover 190, and is secured to the link 184 with the cover over the link facing end of passage or bore 188, said cover 190 being secured between the housing 186 and an angle bracket 192 by means of bolt means 194 to the link 184. A link 184 can be chosen as one which includes as a part thereof bracket 192. Passageway 188 has an enlarged portion 196 which receives a coil spring 198 serving to bias pinch-finger 200 normally outward of the housing 186 through mouth 202 of passageway 188. A snapring 204 is secured to finger 200 so that one side thereof retains the pinch-finger bias outward of the housing a predetermined distance while the other side of the snapring serves as a seat for coil spring 198. If the finger 200 were not restricted by snapring 204, it would engage the web momentarily depressing same and causing a downward pull or deflection of the web causing the web to be deformed by stretching, pinching, etc., as will be explained hereinafter. A plurality of such described pinch-finger assemblies are provided along the length of link chain 180 at equally spaced intervals thereon. As is shown in FIG. 4, the lower reach of the pinch-finger transport mechanism 150 has all of the pinch-fingers engaged upon the laminated web 65 along the line at which the pinchfinger ends are parallel and exert a drawing force upon the web as the fingers travel with the chain 180. The remaining pinch-finger assemblies of pinch-finger transport mechanism 150 are on the upper reach of the sprocket chain 180.

The borders of webs 64 and 66, as well as of web 65, preferably are maintained at least at one-quarter inch so that there is no danger of the pinch-fingers 200 impacting upon the web 65 in a coated or in a laminated area. This is especially important at increased speed of operation of machine 10 where some problem of mismatch may occur.

The movable pinch-finger transport mechanism 156 is substantially identical to the fixed pinch-finger transport mechanism 154 except that the races 170, 172 of bearings 166 and 168' extend outward a sufficient distance to receive the setscrews 206 and 208 therein. In this manner, release of the said screws 206 and 208 permit the entire mechanism 156 to be moved laterally so as to be adjustable for various width webs and yet remain at the border 160 thereof. The pinchfinger assemblies 182 individually are mounted so as to align with the corresponding pinch-finger assemblies 182 on pinchfinger transport mechanism 154.

The diameter of housing 186 is selected to be greater than the length of a single link 184 of the link chain 180 so that the ends of the links adjacent thereto are engaged whereby to prevent tipping of the pinch-finger assembly which may result in erroneous angular engagement of the pinch-finger with the web. Similarly, housing 186 of pinch-finger assembly 182 has a diameter identical to the diameter of housing 186 of pinchfinger assembly 182 and has the same relationship with link 184' and chain 180 as housing 186 has with link 184 and chain 180.

It should be noted that because the laminated web 65 is comprised of laminated portions and nonlaminated portions and presents a tacky plurality of adhesive lines 124 to the pinch-fingers 200, it would be desirous, theoretically, that said fingers would be impressed against the web at the unlaminated portions thereof and between lines 124 so as to leave undisturbed the same. Otherwise, both the adhesive lines 122 and 124 would be smeared, widened or otherwise deformed, and result in border waste. However, such waste is still well below that experienced in prior machines. For small cell sizes, like /s-inch cell, one cannot avoid such waste. For larger cell sizes, such as one-fourth inch, one may, by selection of the proper pitch chain, and proper spacing of pinch-fingers, achieve such theoretical goal.

The other portion of the draw mechanism 148 is the lower reach shuttle bar transport mechanism 152. A pair of support bars 210 and 212 are mounted spaced apart on bearings 216 and 218 having the inner races 214 and 215 mounted on shaft 136. A sprocket gear 220 with sprocket teeth 222 is mounted for rotation with shaft 136 between support bars 210 and 212. Obviously, a similar arrangement is disposed at the opposite end of the support bars 210 and 212 at the input end of draw stage 16 and mounted on shaft 134. Likewise and also mounted to respective shafts 136 and 134, it is a second, lower reach shuttle bar transport system 152' identical to the shuttle bar transport mechanism 152. The shuttle bar transport mechanism 152 may be positioned on shafts 134 and 136 so that the movable pinch-finger transport mechanism is generally aligned therewith when the same is at its maximum distance from the fixed pinch-finger transport mechanism 154, the sprocket teeth 222 being generally vertically aligned with the sprocket teeth 176.

Link chain 224 is mounted on sprocket gears 220 and a similar link chain 224' (not shown) is mounted on the sprocket gears of transport assembly 152'. Alternate links 226 and 226' of chains 224 and 224 carry opposite ends of shuttle bars 228. The shuttle bars 228 each comprise a T-shaped member having a planar leg 230 and a depending portion 232 integral therewith and arranged at right angles relative to base 230. Leg 230 has opposite ends 234 and 236 which are secured by means of brackets 238 and 240 which may or may not be a part of the link 226 and fastening means 242, to alternate ones of the links 226 and 226. The leg 230 has its planar upper surface at right angle to pinch-fingers 200 of respective pinch-finger transport mechanisms 154 and 156. Depending portion 232 of shuttle bar 228 serves as a strengthening portion and is formed of a configuration that will not interfere with the movement of said shuttle bars between the transport mechanism 152 and 152'. Clearly, shuttle bars 228 may be formed as solid pieces, L-shaped pieces, etc., so long as a planar surface is presented to the pinchfinger.

The shuttle bars are arranged parallel one relative to the other bridging the bed of the laminating machine 10. Al-

ternate shuttle bars act as backing means when the pinch-fingers 200 are impressed on the web, whereas the other, remaining, shuttle bars serve as support means for the web 65 at those locations where not impressed by the pinch-fingers 200.

The rate of travel of the pinch-finger transport mechanisms 154 and 156 as well as the shuttle bar transport mechanisms 152 and 152 must be maintained identical. Adjustment in the tension of the chains thereof is provided by idler sprocket gear pairs 244 on the pinch-finger transport mechanism and 246 on the shuttle bar transport mechanism. Since the shafts 130, 132, 134 and 136 are all driven by rotation of reducer gear 142, the respective transport mechanisms of the draw stage 18 will be driven at the same rate.

The width dimensions of the legs 230 of shuttle bars 228 are selected similar one to the other and the arrangements of the pinch-fingers on the pinch-finger transport mechanism and the shuttle bars on the shuttle-bar transport mechanism are selected so that the pinch-fingers ideally will impinge upon the laminate web 65 at the borders thereof and between areas where adhesive has been placed. For most practical usage, and especially where small cell.sizes are concerned, the latter is not critical. Backup plates 248 preferably are utilized between shafts and 132 and 134 and 136 and between the sprocket-wheel mounting assemblies. These backup plates 248 include a leg portion 250 so that the links are braced when the pinch-fingers 200 impinge on the web laminate 65. The backup plates 248 which are utilized associated with the movable pinch-finger transport mechanism 152', are mounted for lateral movement on the respective shaft of the respective transport mechanism so that it may be actually movable therealong serving as bracing means for this sprocket chain at the areas that the pinch-fingers engage the web.

A tip 252 formed of resilient material may be fitted onto the end of the pinch-fingers 200 for better gripping function. Another advantageous expedient is to have the pinch-finger transport system slightly elevated at the input end of the draw stage 18. An elevational difference approximately oneeighth inch at the input end of the pinch-finger transport system 148 insures that the pinch-fingers 200 grip the laminate web 65 with increasing pressure as the web 65 passes toward the discharge and from the input end of stage 18. This result may be due to the increased compression of spring 198 as the pinch-finger assemblies 182 travel with movement of the sprocket chains.

Another preferred expedient may be to position the pair of pinch-finger transport mechanisms 154 and 156 a slightly increased distance apart on the shaft 132 at the discharge end of the draw stage 18. This expedient produces a lateral tension perpendicular to the web path in which the web 65 tends to straighten and be smooth so as to prevent blousing or sagging in the center as the pinch-fingers 200 engage the web and travel away from the input end of the draw stage 18 since the pinch-fingers also are moving slightly apart. This expedient last mentioned is advantageous in that the web 65 is maintained reasonably straight and flat in traveling through the draw stage 18 for discharge toward the severing stage 20; and can be accomplished by skimming the blocks making up beam pair 126.

Both the printing stage 16 and the draw stage 18 of laminating machine 10 are driven by drive means 24. Drive means 24 comprises a single DC motor 26 arranged mounted to the base beams 40 of frame 12 of laminating machine 10. A sprocket gear 253 is mounted on the motor shaft 254. The motor is located so that the gear 253 is disposed to extend outward from the side of the laminating machine 10, adjacent to the movable pinch-finger transport mechanism 156. A shaft 256 joumaled for rotation on mounting means (not shown) secured to the adjacent one of beam pair 32 and between horizontal beam pairs 40 and 38. A sprocket gear 258 is mounted at one end of shaft 256 and aligned in a common vertical plane with gear 253. At opposite end of shaft 256, there is mounted a sprocket gear 260. The gear 260 as well as the gears 253 and 258 rotate in a clockwise direction as viewed in FIG. 1 and illustrated by the arrows. Chain drive 262 is mounted on gears 253 and 258. A second chain drive 264 is mounted respectively to reduction gear 142 and over sprocket gear 80" and tangential to sprocket gear 82", which is keyed to a timing gear 82' mounted on shaft 84 adjacent to gear 82". The direction of travel of the chain drive 264, too, is clockwise so that the printing rollers 80 and 82 are driven in clockwise and counterclockwise directions, respectively.

Idler gear arrangements are provided as the adjustment means 28 in order to adjust the tension of the chain drive 264, said means including a reduced diameter sprocket gear 266. Obviously, gear 266 is arranged in the same vertical plane as gear 260. It has been experienced that with a 3 horsepower, s.c.r. speed controlled, 220-volt direct current variable speed motor 26 utilized in one embodiment, the machine may be made to operate at speeds on the order of feet of web passing through the print and draw stages per minute. The speed can be varied considerably by different gear and drive arrangements and/orcontrol settings.

Attention now is directed to the severing stage which receives the laminated web 65 from the draw stage discharge end so that the laminated web is severed transverse thereto and along the line taken through an unlaminated portion of the web 65 and between lines 124 on the upper surface thereof, parallel and equal spaced from the adjacent laminated portions and lines 124. Great care should be exercised to assure that the point of severance occurs repetitively along a line having the same relative distance from adjacent adhesive-carrying areas on the upper and lower faces of web 64 of laminate web 65. It should be understood that the web 65, as it passes from the printing stage, carries an upper surface tacky adhesive lines and has an adhesive-free undersurface. it is essential that both the impingement of the pinch-fingers 200 and the severing line occur on the nonadhesive portions of the web so that the severed product is satisfactory in precise locations of the adhesive lines 122 and 124.

The severing stage 20 is mounted across the bed of the laminating machine 10 and between vertical beam pairs 34. Said severing stage 20 comprises a stationary upper blade assembly 268 and movable lower blade assembly 270. The upper blade assembly 268 includes a mounting 272 by which it is secured to the frame portion 34 across the bed of the machine 10 so that the blade 274 is above the bed 65. A second support means 276 likewise is secured to respective ones of the pair of beams 34 also bridging the bed of the machine. Bore means are provided in both supports 272 and 276 to accommodate limited movement of vertical shaft 280.

The lower blade assembly 270 comprises a substantially rectangular end portion 282 having one side thereof including the blade 284. The block 282 is mounted fixedly on the collars 286 so as to be movable therewith. The lower end of shaft 280 is connected to link 288 which in turn is connected to an air cylinder 290 by means of an articulated pivotal linkage as shown at 292. Microswitches 294, 410 are provided and adapted selectively to be engaged by one arm 296 of linkage 292 when the blade 294 is in its lowest position. The air cylinder 290 is mounted on plates 298 secured to and between beam pair 34. A DC solenoid valve pair 300 controls the operation of air cylinder 290. Movement of the ram 302 of air cylinder 290 in the direction of arrow 304 causes the linkage to force link 288 and shaft 280 upwards so as to drive the blade 284 in the direction of stationary blade 274. The flats of blades 284 and 274 lie in only slightly spaced parallel vertical planes so that there may be frictional engagement therebetween when the blade 284 is driven upwards toward and engages blade 274. The diagonal surface portions of the blades likewise lie in parallel diagonal planes.

The synchronizing means according to the invention is generally designated by reference character 22 and now will be discussed with particular attention directed to the illustration of FIG. 10 wherein the electrical circuit utilized therefor is set forth. Synchronizing means 22 ensures that the severing of the web 65 is controlled very precisely so as to determine the length dimension of the honeycomb laminate sheets. Means are provided in the synchronizing means to regulate the severing cycle. Both automatic control and manual control are provided as will be seen hereinafter.

Referring now to FIG. 10, there is shown diagrammatically an automatic counting and control system 310 electrically coupled to a blade or knife control system 312 which in turn is electrically coupled to the solenoid valves 300 comprising valves 306 and 307 which are coupled to operate air cylinder 290. The counting and control system 310 is housed within a housing 314 represented by the broken line enclosure. Within the said housing 314 is provided an on-off switch 316, a 12- volt DC filtered power supply 318, an electronic solid-state counter 320, a holding relay 322 and signal lights 324 and 326. A plug 328 is connected to a source of standard 1 l5-volt AC and to the input terminals 330 of switch 316. The output of switch 316 is connected by means of leads 332 and 334, through leads 336 and 338 to the input 340 of DC filtered power supply 318 and to terminals 342 and 344 of solid-state counter 320. The systems 310 and 312 are activated manually by depression of push-to-start" button 325 which momentarily shorts terminals 354 and 356. The proximity control unit includes holding relay 322 consisting of a coil 364 and NO. contact 366, N.C. contact 368 and common contact 369. The positive polarity terminal 370 is connected to one side 372 of relay coil 364 by lead 374. The negative tenninal of power supply 318 is connected to the common contact 369 of relay 322 by means of lead 376. The other end 378 of coil 364 is connected to one terminal of signal lamp 324 by lead 380. in dicating lamp 326 is connected across leads 336 and 338 so that the operating state of the counter 320 is ascertained. Likewise the lamp 324 is connected across the relay 322 and one terminal of the counter 320 so as to ascertain the operating state of the severing stage 20.

The automatic counting and control system 310 is connected to the knife control system 312 by means of a cable shown generally at 382 containing leads 384, 386, 388 and 390. A mode switch and a manual knife control system, both designated generally as 312, is housed in a housing represented by the broken line enclosure 392. The system 312 includes, all mounted in the housing 392, a mode switch 394 with three positions, automatic, off and manual; a manually operated control switch 396, a pair of diodes 398 and 400 and a surge resistor 402 coupled thereto. Lead 384 is coupled between terminal 346 of counter 320 and the first common terminal 401 of switch 394. Lead 386 is coupled from the N.C. contact 368 of relay 322 to a second common terminal 403 of switch 394. The other terminal 378 of relay coil 364 is coupled through leads 380 and 388 to the third common terminal 405 of switch 394. t

The switch 394 can be described as a three-pole doublethrow, center off switch, a term perhaps more familiar, and is operable between the automatic mode and the manual mode. The terminal 404 is coupled to the NO. limit switch 410 and to the solenoid coil of solenoid valve 306. Likewise, the terminal 406 is coupled to terminal 413 of switch 396 and through N.C. limit switch 294 for manually moving the lower blade 284 down. Terminal 408 of switch 394 is coupled to terminal 411 of switch 396 and to the other terminal 419 of limit switch 410. Diodes 398 and 400 and surge resistor 402 are coupled into the circuit of the system 312 to prevent retriggering the solid-state output of the counter 320 with the back EMF generated when the coils of solenoid valves 306 and 307 suddenly are deenergized. One end of the resistor 402 is coupled through lead 412 to one terminal 414 of solenoid coil 306 and through lead 390 to lamp 324.

Diodes 398 and 400 are connected in parallel to the other end of resistor 402. Diode 398 is coupled through lead 416 to the other terminal 417 of solenoid coil 306 and to the N.C. terminal 418 of the limit switch 410 through extension lead 416. Diode 400 is coupled through lead 420 to one terminal 422 of the return solenoid valve coil 307, and to return limit switch 294 through lead extension 420'. When the switch 394 is in automatic mode, the counter 320 controls the movement of blade 284. When the switch 394 is set for manual, the switch 396 controls the movement of blade 284. This setting is accomplished by effecting contact between terminal 403 of switch 394 and common terminal 415 of switch 396 through lead 407.

In the automatic mode, when the counter 320 receives the predetermined count as will be explained hereinafter, a triggering pulse generated by the counter through terminal 346 is transmitted through limit switch 410 back to the coil 364 of holding relay 322. Upon being closed, terminal 366 of relay 322 feeds a shorting pulse to terminal 354, effectively bridging terminals 354 and 356 which nearly instantly recycles the counter for the next count. The solenoid coil 306, the holding relay coil 364 and lamp 324 are connected in parallel and are all in series with terminal 366 and switch 410 so that when the blade 284 is raised to sufficient height to allow limit switch 410 to open, breaking the circuit path, the relay 322 returns to its normal state, solenoid valve 306 closes and lamp 324 is deenergized. When solenoid valve 306 is energized, the cylinder 290 is actuated for moving the ram 302 to drive the blade 284 toward the fixed blade 274 for severance of the web.

When the relay 322 drops out, a circuit through solenoid valve 307 is closed through the return limit switch 294 now closed because blade assembly 270 is displaced therefrom. As long as the knife is removed from the return limit switch 294, the return solenoid valve 307 is energized, returning the ram 302 to drive the lower blade arrangement 270 downward until it closes the return limit switch 294 thereby deenergizing the return solenoid valve 307 stopping the knife arrangement 270.

Now, attention is directed to the means for monitoring the web so as to control the length of the sheets discharged from the machine 10. The gear 424 is mounted on shaft 83 adjacent plate 78. Gear 424 has teeth 426 along the circumferential peripheral edge thereof and extending radially outward therefrom. Teeth 426 are spaced identically with the spacing of lands 118 of the printing roll 80. Said gear 424 is mounted onto shaft 83 so that the teeth 426 are exactly aligned with the lands 118 of roller 80. A proximity detector 428 or similar sensing means is mounted to the frame 12 of laminating machine directly upon the horizontal beam 38 so that the sensing probe 430 thereof is in close proximity to the path followed by the ends of the teeth 426 on rotation of gear 424 and may be adjusted, see arrows 429, to achieve cutting registration so that severance is effected unlaminated areas of web 65. The sensing probe 430 is connected through amplifier 431 to the counter 320. The amplifier 431 has a sensitivity control 432.

Counting of the number of adhesive lines printed by one of the rollers, say upper roller 80 on the upper surface of web 64, for example, effectively measures the elapsed length of the web 65 passing same and thus indicates when the cutting or severing is to be effected in the severing stage for a given length product. The circumferential distance of the printing roller 80 as it rotates easily is translated into linear distance on the moving web 65. The counter 320 is adjusted to trip the blade 284 to its cutting cycle for any number of adhesive lines by presetting it. When the desired number of lands 118 of roller have passed the sensing probe 430 of the proximity detector 428, a triggering pulse is transmitted from the counter to the solenoid valves 306 and 307 which operate the cylinder 290 to drive movable blade assembly 270 through its cycle. For example, the counter is set to react when 166 lines have been printed on one face of web 64; when 166 gear teeth 426 have passed the sensing probe 430 from an initial zero count, the lower blade 284 of the knife arrangement 270 is actuated toward the fixed blade assembly 268. The count then immediately is reduced to zero, and when the 167th tooth passes the sensing means 428, the first count of the next sequence of the 166 count is instituted and impressed on he counter although the knife is still engaged in traveling through its cutting cycle toward the fixed blade 274.

The proximity detector 428 may be mounted so that it can be pivoted in an arc (arrows 429) about the center of gear 424 or, as illustrated, the probe 430 may be slidable in a slot to move back and forth to a desired position and then fixed by bolts 435 (arrows 433) so that one may adjust and/or change the timing of the severing cycle. This character of mounting is advantageous because at the time the signal is given to accelerate and cut the web, there is a finite time delay before the web 65 actually is severed. Assuming a delay of 10 milliseconds from the time the signal is generated by the counter 320 to the time the knife 284 pierces the web 65, such delay will result in a linear displacement of 0. I00 inch in the severed web assuming the web is moving at a speed of IO-inches per second. Therefore, by advancing or retarding the angular location of the detector relative the periphery of the gear 424, the exact time for the severing point relative to location on the web 65 is adjustable much in the manner of a fine tuning adjustment. Compensation has to be increased for increased speeds and reduced at lower speeds. Therefore, whenever the speed of travel of the web is changed, the angular location of the proximity detector 428 also must be changed. As each tooth 426 passes the sensing probe 430 of proximity detector 428, a signal is transmitted from the switch to the counter. The counter is set to provide a triggering pulse after a certain predetermined number of signals have been transmitted thereto so that the length of the sheets produced at the discharge end of the machine 10 is controllable.

Calling attention to FIGS. 8 and 9, there is shown in FIG. 8 a plan view of a block of laminated sheets known as the honeycomb lay up. As seen at the partially removed portions of the figure, when the sheets are stacked with edges aligned, the alternate adhesive lines join one sheet to the other with equal spaces between adjacent laminated portions remaining unlaminated. When expanded into the configuration shown in FIG. 9, we see that the areas of the lines, that is, the adhesive lines bonded one to the other form opposite sides of the hexagonal cell. The unlaminated portions form the other four sides of the hexagonal cell.

One of the important advantages of the laminating machine 10 is its capability to imprint the transverse adhesive lines 122 and 124 perpendicular to the direction of travel of the web for production of laminate sheets for any desired ultimate expanded cell size. This is accomplished simply by utilizing printing rollers and 82 with the width of lands 118 precisely formed. In the embodiment described herein, specifically for manufacturing cell sizes of one-fourth inch, the width of lands 118 is selected to be 0.075 inch. When other cell sizes are desired, the entire printing and laminating stage 16 can be bodily removed from the frame 12 and replaced with another, preassembled, printing and laminating stage carrying printing rollers having lands ofa different width dimension. Thus, for a 3/16 inch cell size, one would require a land width dimension of 0.050 inch so that a glue line of 0.050-inch width is imprinted.

Also while the laminating machine 10 has been described as operating upon a pair of webs 64, 66, it is contemplated that the invention is capable of use upon multiple web pairs with adjustments within the skill of the art from the disclosure herein.

What it is desired to be secured by letters patent of the United States is:

1. A method of making unexpanded honeycomb laminate sheets by imprinting one of a pair of continuous webs with transverse lines of adhesive in parallel, spaced relationship on the upper face thereof, then imprinting transverse lines of adhesive in parallel, spaced relationship on the lower face of said one web but at areas on said lower face below the unprinted portions of the upper face so that the unprinted areas on both faces are of like width and, simultaneously with lower face printing, causing the one web to be laminated to the other of said pair of webs to form a web laminate and causing said web laminate to be severed into lengths of predetermined dimension to form said sheets.

2. A method of making unexpanded honeycomb laminate sheets comprising the steps of drawing a pair of webs of sheet material from a source thereof, aligning said pair of webs so that their edges are aligned, feeding said aligned pair of webs to a printing mechanism, imprinting transverse spaced parallel lines of adhesive along the underface of one of said webs, then imprinting similar transverse spaced parallel lines of adhesive on the upper face of said one web but intermediate the unprinted area of the under face, simultaneously with said second printing bringing said imprinted web into contact with the other one of said pair of webs and exerting pressure upon said webs to form a laminate web, thereafter severing predetermined lengths from said laminate web to form said sheets.

3. The method as claimed in claim 2 in which said web laminate is drawn positively from the printing mechanism at a rate slightly faster than the rate of operation of the printing mechanism.

4. The method as claimed in claim 2 in which the severance is effected as a function of the number of lines printed upon the said one web.

5. The method as claimed in claim 2 in which the severance is effected by directing a blade to the underface of the laminate web and between areas of imprinting. 

2. A method of making unexpanded honeycomb laminate sheets comprising the steps of drawing a pair of webs of sheet material from a source thereof, aligning said pair of webs so that their edges are aligned, feeding said aligned pair of webs to a printing mechanism, imprinting transverse spaced parallel lines of adhesive along the underface of one of said webs, then imprinting similar transverse spaced parallel lines of adhesive on the upper face of said one web but intermediate the unprinted area of the under face, simultaneously with said second printing bringing said imprinted web into contact with the other one of said pair of webs and exerting pressure upon said webs to form a laminate web, thereafter severing predetermined lengths from said laminate web to form said sheets.
 3. The method as claimed in claim 2 in which said web laminate is drawn positively from the printing mechanism at a rate slightly faster than the rate of operation of the printing mechanism.
 4. The method as claimed in claim 2 in which the severance is effected as a function of thE number of lines printed upon the said one web.
 5. The method as claimed in claim 2 in which the severance is effected by directing a blade to the underface of the laminate web and between areas of imprinting. 